The search for Lisa Irwin hit closer to home this week as cadaver dogs have picked up the scent of human remains next to the her parent's bed, according to a police affidavit.

But an attorney for the family said following the cadaver dog's nose may be misleading investigators.

"My understanding is that there are cold cases where dogs have hit on scents of decomposition that have been in the home for as long as 28 years," said Cyndy Short, in an exclusive interview with "Good Morning America." "This is an old home. 63 years old. There could be a lot of other explanations for that."

But Brad Garrett, an ABC News consultant and former FBI special agent, said cadaver dogs are typically accurate.

"In studies done of cadaver dogs where the dog has direct access to the scent and its reasonably fresh - its above 90 percent.

The affidavit, released on Friday, revealed that a cadaver dog searching for evidence for missing the 11-month-old "indicated a positive 'hit' for the scent of a deceased human" next to her mother's bed.

The affidavit was filed with a Kansas City court to request a search warrant of the family home.

The search was conducted Wednesday and police left with several items, including a large portion of carpet.

"The only areas extensively processed for DNA and fingerprints during the consent were the baby's bedroom and possible points of entry," the document states.

"The extent of the search had been limited in nature with consent" of the parents, police stated in the request for the search warrant.

The cadaver dog that searched the home on Oct. 17 with the parents' agreement "indicated a positive 'hit' for the scent of a deceased human in an area of the floor of Bradley's bedroom near the bed," the affidavit stated. The consistency and accuracy of cadaver dogs has been challenged in past cases.

The document also contained a puzzling comment by Lisa's mother. "Bradley made the statement she did not initially look for her baby behind the house because she 'was afraid of what she might find,'" it said.

In addition, the police cited a "garden area with portions of dirt having an appearance of being recently disturbed or overturned."

The affidavit lists items that investigators took from the house, including a multicolored comforter, purple shorts, a Disney character shirt, a glow worm toy, a Cars-themed blanket, rolls of tape and a tape dispenser.

Bradley has previously told investigators that Lisa was wearing purple shorts and a purple t-shirt when she last saw her on the night of Oct. 3, the night Lisa vanished.

The document also revealed that inconsistent stories from the "people involved" may have hampered the early stages of the investigaton.

"Investigative interviews with the people involved revealed conflicting information for clear direction in the investigation," the affidavit said.

Earlier Friday, three witnesses in two Kansas City locations told "Good Morning America" they were convinced they saw a man carrying a baby matching Lisa's description the night she disappeared from her Missouri bedroom.

Mike Thompson told ABC News that he was on his way home from work around 4 a.m. on Oct. 4 when he saw a man in a t-shirt carrying a baby at an intersection about three miles from the Irwin home.

It was shortly after 4 a.m. that Lisa's parents said they discovered she was missing.

"[At] 4 a.m., 45 degrees, baby don't have a coat or nothing and this guy is walking down the street and I thought it was kind of weird," Thompson said.

He thought the sight was so unusual that he recalled considering offering the man and baby a ride home, but couldn't because he was on his motorcycle. He later reported what he saw to police and told ABC News he is convinced the baby was Lisa.

Thompson described the man as around 5-feet-7, between 140 and 150 pounds and in his late 30s or early 40s.

A few hours earlier, a couple living three houses down from the Irwin family said they saw a similar sight. A woman and her husband said they saw a man in a t-shirt carrying a baby. They thought the situation was so unusual that they reported it to police on the morning of Oct. 4.

"It was shocking because I couldn't imagine anyone outside walking with their baby in the cold like that with no clothes on," the woman told ABC News.

Bradley has said that Lisa was wearing purple shorts and a purple t-shirt when she last saw her, but the neighboring couple said they baby they saw did not appear to be wearing any clothing.

"We seen the little arm, the leg, it didn't look like the baby had on any clothes, just a diaper," she said.

New Developments in Baby Lisa Investigation

The woman said police have interviewed her four times and police say they are still looking into the possible sightings.

"That is something that we've followed up on," said Kansas City Police Department Sgt. Stacey Graves. "We've haven't discounted it and we have no reason to believe that they didn't see what they said that they saw."

The focus of the investigation this week has been largely centered on Lisa's parents.

The couple has retained two lawyers: well-known New York defense attorney Joe Tacopina and a local Kansas City attorney.

An anonymous benefactor is offering a $100,000 reward for Baby Lisa's safe return or the conviction of whoever took the little girl.